I stumbled across this site today ( http://www.pegtop.net/delphi/blendmodes/ ) which has code and visual example for various layer blending modes. Some more texture blend modes (other than add, mul, sub, blend) would be great in Blender and would make texturing a lot more flexible and useful without having to switch back and forth between image editors so much. I had a look at the code myself (src/texture.c) to see if I could add any, but unfortunately it was over my head. If anyone's interested in giving it a go, you'd be very welcome

Indeed, some neat color blending functions. I wonder how useful most of them would be in practice, though. They certainly all have their place in texture creation, but only a few of them would be useful for texture mixing in a 3d application (IMHO).

Anyway, in short, I think that a few of those would be an useful addition to the blender color mixing functions.

While on that topic: Would it be terribly hard to implement some sort of eyedropper tool? Something which a) can be used to click at anything on screen to grab the color of that pixel, and b) which stores the currently 'eyedropped' color so that one could easily assign that value to any of the color controls (i.e. mir, spec, col, texture rgb-slider, vertexpaint etc - sort of "rightclick on SPEC-colorchip to put the current eyedropper color there")

In paintmode one can actually right-click to grab the color, but nowhere else that I can recall.